John Kerry is set to arrive in Israel on Monday evening. | Palestine Monitor

The armed wing of Hamas said it captured an Israeli soldier late Sunday, a claim the Israeli military has not confirmed. More than 500 Palestinians and 18 Israeli soldiers have been killed since Operation Protective Edge began two weeks ago.

The Al-Qassam Brigades, the military branch of Hamas declared that they captured Israeli soldier Shaul Aron on Sunday night. Israeli Ambassador to the UN Ron Prosor dismissed the statement, according to Al Jazeera.

The Al-Qassam brigades did not clarify whether the soldier was captured dead or alive. News of the kidnapping sparked celebrations across the West Bank, East-Jerusalem, and the Gaza Strip, Ma’an News reported.

Gilad Shalit, an Israeli soldier, was held captive in Gaza during 2006-2011. Hamas brokered the release of more than 1,000 Palestinian prisoners in exchange for Shalit. At the moment over 5,000 Palestinians are kept in Israeli prisons.

By Monday evening, at least 50 Palestinians were killed as the Israel's Operation Protective Edge entered its 14th day, according to Ma’an News Agency.

The victims included three extended families. Five members of the al-Yaziji family were killed in strikes in the Gaza city. Eleven members of the Siyam family in Rafah were pulled out of the rubble after their house was destroyed in an airstrike. In the Khan Younis neighborhood, 16 members of the Abu Jami family died under Israeli bombing.

Hamas said its fighters destroyed an Israeli army jeep in retaliation for Israeli attacks on the Shujaiyeh neighborhood on Sunday.

Members of Al-Qassam brigades arrived to southern Israel through tunnels from the northern part of the Gaza Strip on Monday. Israeli forces reported they “killed more than ten terrorists”.

Sunday became the bloodiest day so far, as more than 150 Palestinians were killed. Over 500 Palestinians have lost their lives since the beginning of Israel’s operation in Gaza. The UN says majority of the victims are civilians.

At least 20 Israelis, mostly soldiers, have also died in the operation.

Over 83,000 people have sought shelter at UNRWA (United Nations Work and Relief Agency) schools in the Gaza Strip, according to the organization’s spokesperson Chris Guinness. The amount of people seeking shelter has increased by 400% in the last four days. UNRWA has appealed for $60 million international aid for Gaza.

The number of people fleeing Israeli attacks in Gaza has surpassed the amount during Operation Cast Lead in 2008-2009, Electronic Intifada reports.

The UN Security Council called for an immediate cessation of hostilities in its meeting on Sunday. The UN Secretary General Ban Ki-moon demanded Israel to “exercise maximum restraint”.

The US President Barack Obama has raised concern of the increasing number of casualties on both sides.

US Secretary of State John Kerry traveled to Cairo on Monday to work on a ceasefire between the two parties. Haaretz reported that Kerry was coming to Israel later on Monday.